handling Throw exception in Rust 1.55

In Rust, throwing an exception is known as "panicking". Exceptions are thrown with the panic! macro. Here is an example of using panic! to raise an exception with a custom message:

fn main() {
    let x = 42;
    if x > 100 {
        panic!("Value of x is too high!");
    } else {
        println!("Value of x is {}", x);
    }
}

In this example, if the value of x is greater than 100, the program will panic with the custom message "Value of x is too high!". Otherwise, it will print the value of x.

You can also use panic! to raise exceptions without custom messages:

fn main() {
    let x: Option = None;
    let y = x.unwrap();
}

In this example, we attempt to unwrap a None value, which will result in a panic with the default error message "called Option::unwrap() on a None value".

It's worth noting that panicking should be used sparingly in Rust, as it can make it difficult for other code to recover from errors. In general, it's better to use Rust's built-in error handling mechanisms (Result and Option) to handle errors in a more structured way, rather than relying on panicking.